Patients wishing to complain about their local hospital receive poor information that is inconsistent, the health service ombudsman has said.

Ann Abraham, who has published a report detailing "harrowing" complaints about elderly care in the NHS, told the Commons Health Committee: "Improving complaints information is one of my particular priorities at the moment."

If a complaint is not resolved by a local NHS trust, patients have the right to ask the ombudsman to step in, but Ms Abraham said: "It takes considerable tenacity to see a complaint through all the way to the ombudsman."

Of the current system for handling complaints at a local level, she said: "No it's not great, there's a huge amount of work to do and some of that's cultural but I do think we are in a better place now than what we have been."

Ms Abraham defended the fact only 3% of complaints referred to her office are fully investigated. She said the office saw "many thousands of complaints" but quite a substantial number are "premature" - with no complaint made first to the local health trust or GP practice.

She said it was right that the first stage of the complaints process gave the hospital or NHS organisation the chance to respond. But when challenged on the reasons why so many patients give up on their complaints to NHS trusts, she said the health service still had a lot to learn.

"It's just so extraordinary when you think of so many organisations who would think that kind of feedback was gold dust when it comes to improving their services.

"I don't get very depressed very often but there are two things I hear far too often. One is complainants who say 'It's not worth speaking up, nothing ever changes' and the other is a clinician saying 'Well, I've heard everything and I'm sure you are distressed but I would not have done anything different'."

Today's ombudsman report detailed 10 complaints which showed neglect of even the "most basic" human needs. One detailed how a patient, transferred by ambulance to a care home, arrived bruised, soaked in urine, dishevelled and wearing someone else's clothes. In another case, a man's life support system was switched off despite a request from his family to delay doing so for a short time.

Ms Abraham warned these were not isolated incidents and the NHS needed to undergo an urgent widespread change in attitude towards older people.